The U.S.-Russian deal is set to take effect Monday.

Smoke from explosions rises during fighting in the village of Jubata Al Khashab, held by Syrian rebel groups fighting to overthrow President Bashar al-Assad.

BEIRUT, Sept 11 (Reuters) - Syrian rebel factions will issue a statement welcoming the U.S.-Russian deal for a ceasefire and aid deliveries in Syria but with reservations about the handling of violations by the government side, a rebel official said on Sunday.

Fierce fighting and air strikes continued in several parts of Syria a day before the humanitarian truce comes into effect, Syrian state television, rebel groups and a war monitor said.

“The factions welcome a ceasefire and welcome the incoming of aid, but have reservations about some points... what are the sanctions if the regime doesn’t abide by it?” said Zakaria Malahifji of the Aleppo-based rebel group Fastaqim.

Rebel groups believed they are treated unfairly by the deal and complain they were not consulted about it, Malahifji said. “A big part of the agreement serves the regime and doesn’t apply pressure on it and doesn’t serve the Syrian people,” he added.

The ceasefire will not apply to the jihadist groups Islamic State or Jabhat Fateh al-Sham, previously known as the Nusra Front until it broke formal allegiance to al Qaeda and changed its name.

The U.S. on Saturday warned insurgents they would face “dire consequences” if they cooperate with Jabhet Fatah al-Sham, which fought alongside a range of mainstream and Islamist rebel groups during intense battles in recent weeks in southern Aleppo.

More air strikes hit Aleppo and Idlib province on Sunday after scores of people were killed in aerial bombardment on Saturday.

One strike in the town of Saraqeb hit a civil defense center where civilian rescuers are based, injuring several, the Syrian Observatory for Human Rights, a U.K.-based monitor of the war said.